Ball-bearing screw



' J. HOPE.

BALL BEARING SCREW.

APPLICATION man FEB. 5. 1920.

1 357,562, v Patented Nov. 2, 1920.

Fi -.1. Fi --2 INVEN 2-05 I simplify the construction of such a ball- STATES PATENT OFFICE.

JOHN HOPE, F PROVIDENCE, RHODE ISLAND.

BALL-BEARING- SCREW.

Specification of Letters Patent.

Patented Nov. 2, 1920.

Application filed February 5, 1920. Serial No. 356,364.

To all 10 hom it may concern.

Be it known that I, JOHN Horn, a citizen of the United States, residing at Providence,

in the county of Providence and State of form of ball-bearing is inadequate, as forinstance, when the end of a shaft turns in a ball-bearing, the hardened balls will wear out the end of the shaft or throw the shaft out of its required accurate position."

The object of my invention is to construct a ball-bearing screw and a shaft or its equivalent in such a way that a ball, intermediate a row of balls and the end of the shaft, will revolve on the row of balls and turn with the shaft, thereby eliminating all wear on the shaft.

A further object of my invention is to bearing screw and shaftfthereby reducing the cost of manufacturing the same.

My invention consists in the peculiar and novel construction of a ball-bearing screw and shaft, said screw and shaft having details of construction, as will be more fully set forth hereinafter and claimed. M

Figure 1 is a side view of my improved ball-bearing screw.

Fig. 2 is an end view ofthe screw. 1 Fig. 3 is an enlarged detail sectional View taken longitudinally through the ends of the screw and shaft and Fig. 4 is an enlarged transverse sectional View taken on line 4. 4 of Fig. 1 looking in the direction of the arrow at at the row of balls.

In the drawing 5 indicates my improved ball-bearing screw and 6 a shaft or its equivalent having in'its end'a cone-shaped cavity 7, the'wallsof which are preferably at'an angle of forty-five degrees. I

The screw 5 has a head 8, screw-threaded portion 9 and reduced shouldered end portion 10 which has a flat end 11. A collar 12 having a" slightly contracted open end 13 is forced on to the shouldered end'lportion 10 and with the flat end 11 forms a ball raceway 1 1, as shown .in Fig. 3. A

row. of small balls-15. 15 are held in the raceway 14: and a large ball 16 rotates on enters the cone-shaped cavity 7 in the end of the shaft 6, the interior diameter of the collar 12 is larger than the diameter of the large ball 16, and the contracted open end 13 holds the balls in the end of the screw.

When in use the screw 5 screws through a fixed member, not shown, and after adjustment may be locked in the adjusted position by a nut, not shown, on the screw, bearing against the fixed member. The shaft 6 may also represent the hub of a wheel, pulley or any revolving member. In re- 'VOlVlIlg' the shaft 6 the large ball 16 revolves with the shaft and on the row of small balls 15. 15 thereby preventing wear on the. shaft, and as the large ball touches only on the row of small balls, friction is reduced to a minimum. The shaft 6 may also be revolved at an angle to the bearing,

as shown in broken line's in Fig. 3, and accomplish the same valuable result.

It is evident that my improved ball bearing screw can be used for an innumerable number of purposes, such as forming the centers in the head and tailstock of a lathe, 860.

Having thus described my invention I- claim a new 1. A ball-bearing screw having a head L end, a screw-threaded portion, a; reduced shouldered end portion having a fiat end,

a collar on the reduced shouldered end portion, a raceway formed by the fiat end of the shouldered end portion and the collar, a Fow of small'balls in the raceway, a large ball in contact with the row of small balls and out of contact with the collar, said 001- lar having a contracted open end, whereby the balls are held in their operative position in the end of the screw.

2. A ball-bearing structure comprising a screw having a head, a screw-threaded ortion, an end in which is a cavity with aall raceway, a row of small balls in the ball raceway, a large ball in contact with the row of small balls and out of contact with JOHN HOPE.

have signed my 

